1. Field of the Invention
The invention relates to a semiconductor device and a method of fabricating the same.
2. Description of Related Art
As semiconductor devices are integrated, in order to achieve high density and high performance, it is preferred to form a structure stacked upward when fabricating the semiconductor devices, such that the wafer area can be used more efficiently. Therefore, semiconductor structures having a high aspect ratio are commonly seen in small-sized devices. For example, the semiconductor structure includes trenches with a high aspect ratio, for example.
Generally speaking, fabrication of the device includes filling a conductor layer into the trenches with a high aspect ratio. However, since the conductor layer itself does not have a preferable gap-filling ability, unevenly distributed voids are easily formed in the trenches, resulting in a negative influence on electrical testing of the semiconductor device. Besides, the voids may generate unbalanced stresses at two sides of the trench, thus resulting in microbending of the semiconductor structure between the trenches and consequently making the alignment in a subsequent photolithography process more challenging. Thus, how to prevent voids in the trenches with a high aspect ratio and avoid microbending of the semiconductor structures is certainly an issue to work on.